PAY ATTENTION MY QUESTION ASK FOR RADIATION!!!
You sit with friends around a campfire, roasting marshmallows. Which
transfer of thermal energy involved in this system is an example of radiation

Answer:

A. The hand must move with a velocity of 6.98 m/s to break the board.

B. Average force on the hand = 1025 N

Explanation:

A.To determine the speed the hand must move with to break the board, the force workdone in breaking the board is found first.

Workdone = force × distance

Minimum force required = 870 N;

Distance moved by board/Deflection in order to break = 1.4 cm = 0.014 M

Workd done = 870 N × 0.014 m = 12.18 Nm or 12.18 J

This work done = Kinetic energy of the hand

Kinetic energy = mv²/2 ; where m is mass and v is velocity

Mass of hand = 0.50 Kg, velocity = ?, K.E. = 12.18 J

v² = 2 KE/m

v = √2KE/m

v = √(2 × 12.18/0.50)

v = 6.98 m/s

Therefore, the hand must move with a velocity of 6.98 m/s to break the board.

B. Average force on the hand

This can be determined using the equation of motion, v² = u² + 2as to find acceleration, since force = mass × acceleration

From the equation of motion, a = v² - u²/2s

At rest, v = 0, u = 6.98, s = 1.2 cm = 0.012 m

a = 0² - 6.98²/ 2 × 0.012

a = -2030 m/s²

Force = 2030 m/s² × 0. 50 kg = 1015 N

Therefore, Average force on the hand = 1025 N

Electromagnetic waves can travel in vacuums.

To find the correct statement among all the options, we need to know more about the electromagnetic wave.

Electromagnetic wave is created from the oscillation of any charge particles like electron, proton, ions etc. .

Thus we conclude that scientists use electromagnetic waves to detect supernovas because electromagnetic waves can travel in vacuums.

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Answer:

a) By [tex]v^2 = u^2 + 2as[/tex] => a= 70291.70.

(b)By [tex]v = u + at[/tex] => t= 1.58 ms.

(c)By [tex]v^2 = u^2 - 2gh[/tex] => H = 46045.92 m.

Explanation:

a) By [tex]v^2 = u^2 + 2as[/tex]

[tex](950)^2 = 0 + 2 \times a \times 0.75\\a = 601666.67 m/s^2\\a/g = 688858.70/9.8 = 70291.70[/tex]

(b)By [tex]v = u + at[/tex]

[tex]950 = 0 + 601666.67 \times t\\t = 1.58 x 10^-3 sec = 1.58 ms[/tex]

(c)By [tex]v^2 = u^2 - 2gh[/tex]

[tex]0 = (950)^2 - 2 \times9.8 \times H\\H = 46045.92 m[/tex]

Solution :

Given expression :

[tex]$\mu_k$[/tex]mgcosθ = mgsinθ − ma

Here, g = 9.8 [tex]m/s^2[/tex] , a = 3.60 [tex]m/s^2[/tex] , θ = 27°

Therefore,

[tex]$\mu_k mg \cos \theta = mg \sin \theta - ma$[/tex]

[tex]$\mu_k mg \cos \theta = m(g \sin \theta - a)$[/tex]

[tex]$\mu_k g \cos \theta = (g \sin \theta - a)$[/tex]

[tex]$\mu_k =\frac{(g \sin \theta-a)}{g \cos \theta}$[/tex]

Mow calculating the coefficient of kinetic friction as follows :

[tex]$\mu_k=\frac{g \sin \theta-a}{g \cos \theta}$[/tex]

[tex]$\mu_k=\frac{9.8 \times \sin 27^\circ-3.60}{9.8 \times \cos 27^\circ}$[/tex]

[tex]$\mu_k=0.097$[/tex]

Answer:

A binary star is a star system consisting of two stars orbiting around their common barycenter.

#keep learning

Answer:

Length = 3.136 meters

Explanation:

Given the following data;

Speed = 345 m/s

Frequency = 440 Hz

To find how long is the tube;

First of all, we would determine the wavelength;

Wavelength = speed/frequency

Wavelength = 345/440

Wavelength = 0.784 m

Next, we would determine how long is the tube using the formula;

[tex] Length = \frac {2n - 1}{4} * wavelength [/tex]

Substituting into the formula, we have;

[tex] Length = \frac {2*1 - 1}{4} * 0.784 [/tex]

[tex] Length = \frac {2 - 1}{4} * 0.784 [/tex]

[tex] Length = \frac {1}{4} * 0.784 [/tex]

Length = 3.136 meters

Answer:

[tex]51.34^{\circ}[/tex]

Explanation:

Given that,

x component of a vector = -12 m

The y component of a vector = -15 m

We need to find the direction of a vector. The direction of a vector is given by :

[tex]\tan\theta=\dfrac{y}{x}[/tex]

Put all the values,

[tex]\tan\theta=\dfrac{-15}{-12}\\\\\theta=\tan^{-1}(\dfrac{-15}{-12})\\\\\theta=51.34^{\circ}[/tex]

So, the direction of vector is [tex]51.34^{\circ}[/tex] to x component.

Answer:

3.0−0.12=2.88 or 2.88÷0.04=72

0.04×3.0=0.12 and 0.04+3.0=3.04

Answer: 2.4 J

Explanation: Khan Academy

Maximum horizontal force that can be applied on the box is 300.32 N.

Mass of the heaviest box that can be pushed on the ramp at constant speed is 105.16 pound.

Kinetic friction is defined as the opposing force exerted by the surface on an object in contact with it, when there is relative motion between the two surfaces.

Here,

Mass of the box, m = 150 lb = 68.1 kg

Coefficient of kinetic friction, μ = 0.45

Maximum horizontal force that can be applied on the box is the kinetic frictional force. Frictional force,

F(k) = μmg

F(k) = 0.45 x 68.1 x 9.8

F(k) = 300.32 N

Now, the box sits on a ramp inclined at 60°

Coefficient of kinetic friction, μ = 0.45

The net force here acting on the box placed in the ramp is due to the kinetic frictional force and the weight of the box.

So,

Frictional force, F(k)' = μmgcosθ

F(k)' = 0.45 x M x 9.8 x cos 60

F(k)' = 2.2M

Weight of the box acting horizontally,

W = Mgsinθ

W = M x 9.8 x sin60

W = 8.5M

Therefore, net force,

Fn = W - F(k)'

Fn = 8.5M - 2.2M

Fn = 6.3M

The total force acting on the box is

F = F(k) - Fn

ma = 300.32 - 6.3M

Since, the box is moving with constant speed, the acceleration, a = 0

Therefore,

300.32 - 6.3M = 0

6.3M = 300.32

M = 300.32/6.3

M = 47.7 kg = 105.16 pound

Hence,

Maximum horizontal force that can be applied on the box is 300.32 N.

Mass of the heaviest box that can be pushed on the ramp at constant speed is 105.16 pound.

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F = 153 N

[tex]\theta = 11.3°[/tex]

Explanation:

Let us define first our directional convention. Anything pointing up or to the right is considered positive and anything pointing down or to the left is considered negative. Now let's look at the components [tex]F_{x}[/tex] and [tex]F_{y}[/tex]:

[tex]F_{x}[/tex] = 350 N - 200 N = 150 N

[tex]F_{y}[/tex] = 180 N - 150 N = 30 N

The magnitude of the resultant force F is given by

[tex]F = \sqrt{F_{x}^{2}+F_{y}^{2}}[/tex]

[tex]\:\:\:\:\:\:= \sqrt{(150\:N)^{2}+(30\:N)^{2}}[/tex]

[tex]\:\:\:\:\:\:=153\:N[/tex]

To find the direction [tex]\theta[/tex], we use

[tex]\tan \theta = \dfrac{F_{y}}{F_{x}}=\dfrac{30\:N}{150\:N}=0.2[/tex]

or

[tex]\theta = \tan^{-1}(0.2) = 11.3°[/tex]

Answer:

Answer:B

Explanation: The answer explains it

The molecules that make up olive oil are longer than those that make up alcohol, so they have more resistance to sliding past one another. The correct answer is option A.

This higher resistance to flow leads to a higher viscosity in olive oil compared to rubbing alcohol. Viscosity is a measure of a fluid's resistance to flow, and longer molecules in olive oil result in stronger intermolecular forces and entanglements. In contrast, rubbing alcohol has shorter and less complex molecules, which allow them to move more freely and exhibit lower viscosity. The molecular structure and intermolecular forces play a crucial role in determining the viscosity of liquids, making olive oil more viscous than rubbing alcohol. Option A is correct.

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Answer:

parasites are creatures the gain benefit off of other animals usually harming them eg:ticks on dogs

Answer:

The angle of minimum deviation is 28.72°

Explanation:

u welcome

Answer:

Δx Displacement

t Time interval

v0  Initial velocity

v  Final velocity

a  Constant acceleration

Explanation:

I dont know if this helps because these are kinda like, examples... hope it helps tho :)

Answer: 113.75

Explanation:

You know

acceleration = a = 3.5 m/s²

time = t = 5 seconds

initial velocity = u = 14 m/s

Unknown is distance = s = ?

Use equation: s = ut + [tex]\frac{1}{2}[/tex] at²

Substitute all the known values inside the equation:

s = (14*5) + 0.5 * 3.5 * 5²

s = 70 + 43.75 = 113.75 m

The car travels 113.75 metres.

Answer:

Decrease occur in kinetic energy.

Explanation:

The kinetic energy decreases when the the Bob swings reaches to the maximum height because the motion of the bob slower down. At maximum height, the kinetic energy decreases whereas the value of potential energy is the highest. The main reason of higher potential energy is that it depends on height of an object while on the other hand, kinetic energy depends on the motion of an object so that's why the value of kinetic energy decreases and potential energy increases at maximum height of the bob.

Answer:

225,000 kilometers per second

Explanation:

Have a nice day

Answer:

Force is the strength or weight of things that depends on movement. The types of forces are conteact force, spring force, applied force, air resistance force, normal force, frictional force, tension force, and non-contact force.

Work done by  man will be A. 640 J

The work-energy theorem states that the net work done by the forces on an object equals the change in its kinetic energy.

according to work energy theorem

Work done = final Kinetic energy - initial kinetic energy

                   = KE (final) - KE (initial )

                   = 1/2 m ([tex]v^{2}[/tex])  - 1/2 m ([tex]u^{2}[/tex])

                  = 1/2 m ([tex]v^{2}[/tex] - [tex]u^{2}[/tex])

                  = 1/2 * 500 * ( [tex]2^{2}[/tex] - [tex]1.2^{2}[/tex])

                  = 250 * 2.56 = 640 J

correct answer is A. 640 J

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Answer:

B

Explanation:

because it take to the thought of a situation

Answer:

d i think

Explanation:

and are u using IXL???

Answer:

if 1 light year was one millimeter then 105,700 light years = 105,700 mm, (or 105.7 meters in case you needed to simplify or something)

Answer:

D_y = 414.38m

Explanation:

D_y = D*sin(x)

D_y = 673m*sin(38°)

D_y = 414.38m

Complete Question

Two parallel conducting plates are separated by 10.0 cm, and one of them is taken to be at zero volts. (a) What is the electric field strength between them, if the potential 8.00 cm from the zero volt plate(and 2.00 cm from the other) is 450 V?

Answer:

[tex]V'=562.5v[/tex]

Explanation:

From the question we are told that:

Separation distance [tex]d=10cm[/tex]

Voltage at 8cm [tex]V_8=450v[/tex]

Generally the equation for Voltage is mathematically given by

[tex]|V|=|E.d|[/tex]

Where

E=electric field

Therefore

At [tex]d=0.8[/tex]

 [tex](450-0)V=E*(0.08m)[/tex]

 [tex]E=\frac{450}{0.08}[/tex]

 [tex]E=5625v/m[/tex]

Therefore

 At [tex]d=10[/tex]

 [tex]V'=Ed[/tex]

 [tex]V'=5625*0.1m[/tex]

 [tex]V'=562.5v[/tex]

Answer:

jsgssbvwsvs

Explanation:

ifmd understand

Answer:

[tex]{ \tt{initial \: velocity, \: u = 0}} \: (at \: rest) \\ { \tt{final \: velocity, \: v = 15 { {ms}^{ - 1} }}} \\ { \tt{time, \: t = 6s}} \\ { \bf{from \: first \: newtons \: equation \: of \: motion : }} \\ { \bf{v = u + at}} \\ { \tt{15 = 0 + (a \times 6)}} \\ { \tt{6a = 15}} \\ { \tt{acceleration, \: a = 2.5 \: {ms}^{ - 2} }}[/tex]

Answer:

A simple pendulum consists of a ball (point-mass) m hanging from a (massless) string of length L and fixed at a pivot point P. When displaced to an initial angle and released, the pendulum will swing back and forth with periodic motion.

Answer:

22.15 N/m

Explanation:

As we know potential energy = m*g*h

Potential energy of spring = (1/2)kx^2

m*g*h = (1/2)kx^2

Substituting the given values, we get -  

(400)*(9.8)*(10) = (0.5)*(k)*(2.0^2)

k = 39200/2.645

k = 19600 N/m

For safety reasons, this spring constant is increased by 13 % So the new spring constant is  

 k = 19600 * 1.13 = 22148 N/m = 22.15 N/m